Recent Advances in the Plasma-Assisted Synthesis of Zinc Oxide Nanoparticles

Abstract

An overview of recent work on the low-temperature plasma-assisted synthesis of zinc oxide (ZnO) nanoparticles is presented and interpreted in terms of gas-phase and surface reactions with illustrated examples. The thermodynamical nonequilibrium conditions allow the formation of chemically reactive species with a potential energy of several eV, which readily interact with the Zn precursors and initiate reactions leading to the formation of nanoparticles or nanowires. The high-quality nanowires were synthesized from Zn powders only upon interaction with moderately ionized plasma in a narrow range of plasma parameters. This technique is promising for the synthesis of large quantities of nanowires with aspect ratios well above 10, but the exact range of parameters remains to be determined. Apart from the ex situ techniques, the ZnO nanoparticles can be synthesized by depositing a film of precursors (often Zn salts or Zn-containing organometallic compounds) and exposing them to oxygen plasma. This technique is useful for the synthesis of well-adherent ZnO nanoparticles on heat-sensitive objects but requires further scientific validation as it often leads to the formation of a semicontinuous ZnO film rather than nanoparticles. Both low-pressure and atmospheric plasmas are useful in converting the precursor film into ZnO nanoparticles despite completely different mechanisms.

Investigating the Role of Classical Ayurveda-Based Incineration Process on the Synthesis of Zinc Oxide Based Jasada Bhasma Nanoparticles and Zn2+ Bioavailability

“…The XRD spectra for JB samples revealed an enriched crystalline nature with intense and sharp peaks representing the interplanar spacing of “ d hkl ”. This spectrum is consistent with ZnO wurtzite crystals generated by high heat and chemical-based flame spray pyrolysis and plasma discharge methods. , All of the lattice peaks, interplanar distance “ d hkl ”, and lattice constants “ a ” for all JB samples corresponded well with the XRD peaks of the hexagonal wurtzite structure of pure ZnO with the space group P 6 3 mc and JCPDS card no. 36-1451 (Table , see the example in Supporting Information S1).…”

In Situ Tracking of Nonthermal Plasma Etching of ZIF-8 Films

“…Moreover, the O 1s/Zn 2p 1/2 ratio suggests the incorporation of oxygen into the film, agreeing with the presence of the carbonyl groups in C 1s spectra and with the probable formation of ZnO upon 2mIm removal, similar to what has been observed in the thermal combustion of ZIF-8 to dope carbon and nitrogen species 34 or even to the ZnO formation from Zn(CH 3 ) 2 in oxygen plasma treatment. 35 As a direct consequence of oxygen incorporation into the film, the C1s component assigned to CO (at 287.9 eV) increases with time, which is a direct observation of carbonyl species being formed on the surface with the etching of ZIF-8.…”

Untitled

“…Four solutions of ZnNPs were prepared in four flasks, added to each solution 45 mL of 1*10 -3 M ZnSO4 then added 5 mL from P. crispum hot aqueous seeds extract in every flask. The solutions were exposed directly to the plasma device with a difference in the exposure time of the plasma for every solution which is (1, 3, 5, and 10) minutes; then the solutions were stored at 4 °C (Primc et al, 2021).…”